Rotary Oscillating and Reciprocating Surgical Tool

This application is a continuation of U.S Application 17/718,563, filed Apr. 12, 2022 and published as US 2022-0338895, which claims the benefit of U.S. provisional patent application serial number 63/180,470 filed on Apr. 27, 2021, the disclosure of each of which is hereby incorporated herein by reference in its entirety.

The present disclosure relates to a powered surgical tool with a cutter adapted to modify tissue such as bone, cartilage and discs. The tool can effect both rotary oscillation and longitudinal reciprocation of the cutter. The tool can also effect driving in a selected one of two rotational directions, as well as both rotational directions.

Currently there exists surgical tools having a rotary cutter adapted to modify tissue such as bone, cartilage and discs in a patient. Such tools, though, present a problem if the cutter encounters fibrous tissue, such as muscle and nerves. Such fibrous tissue can wrap around the cutter and be damaged thereby. Current systems also provided oscillating rotary tools for such surgical procedures, but the mechanisms used to effect oscillation of the cutter during its rotation do not operate smoothly due to the mechanisms used to effect oscillation. An advance in such oscillating tools is represented by co-pending applications: U.S. Non-Provisional Patent Application No. 13/469,665, entitled “Rotary Oscillating Bone, Cartilage, and Disk Removal Tool Assembly, filed May 11, 2012, which is now issued Patent No. 10,194,922, issued on February 5, 2019; U.S. International Application No. PCT/US2013/037071, entitled “Rotary Oscillating Bone, Cartilage, and Disk Removal Tool Assembly”, filed April 18, 2013; U.S. Non-Provisional Patent Application 13/647,101, entitled “Cutting Tool for Bone, Cartilage, and Disk Removal”, filed October 8, 2012, and now issued Patent No. 9,232,953, issued on January 12, 2016; U.S. International Application No. PCT/US2013/063182, entitled “Cutting Tool for Bone, Cartilage, and Disk Removal”, filed October 3, 2013; U.S. Provisional Patent Application No. 62/460,481, entitled “Surgical Rotary Tool”, filed February 17, 2017; U.S. Non-Provisional Patent Application 15/895,352, entitled “Surgical Rotary Tool”, filed February 13, 2018; U.S. Non-Provisional Patent Application 15/932,361, entitled “Surgical Rotary Tool”, filed February 16, 2018; U.S. Provisional Patent Application No. 62/423,624, entitled “Rotary Oscillating Surgical Tool”, filed November 17, 2016; U.S. Non-Provisional Patent Application 15/814,891, entitled “Rotary Oscillating Surgical Tool”, filed November 16, 2017; U.S. Provisional Patent Application No. 62/423,651, entitled “Robotic Surgical System”, filed November 17, 2016; U.S. Provisional Patent Application No. 62/423,677, entitled “Robotic Surgical System”, filed November 17, 2016; and U.S. Non- Provisional Patent Application 15/816,861, entitled “Robotic Surgical System”, filed November 17, 2017, and now issued Patent No. 11,135,026, issued on October 5, 2021. The contents of each of the above referenced applications are herein incorporated by reference.

Such tools are typically small and lightweight, with little room for drive mechanisms. They tend to operate at high cutting speeds for cutting efficiency and are controlled by a surgeon. Oscillations are on the order of at least about 10,000 oscillations per minute (5,000 orbits per minute), and may be 30,000-50,000 oscillations per minute or more. Reciprocation rate is preferably the same. An oscillation is movement of the cutter from one rotational position extreme to its other rotational extreme. Reciprocation is movement of the cutter from one linear movement position extreme to its other linear movement extreme. The cutter configuration and material being removed will determine cutter speed. Because of the high speed and need for precision placement and cutting, the tools need to be smooth in operation with little vibration.

Powered surgical tools for tissue removal are well known in the art as exemplified by the above referenced tools. Such tools typically are configured for operating in one of four modes. A first mode is to effect rotation of an end effector (e.g., a surgical tool such as a tissue cutter) in one direction of continuous rotation. A second mode is to effect oscillating rotation of an end effector in reversing directions of rotation. A third mode is to effect both rotation of the end effector, and simultaneously effect longitudinal reciprocating movement of the end effector. A fourth mode of operation is to effect only longitudinal reciprocating movement of the end effector.

While these tools are effective, they operate in only one mode of end effector movement. An additional tool is needed if the mode of operating needs to be changed, for example, tissue removal to install a screw fastener. There is thus a need for a multi operating mode powered surgical tool that can be used for both tissue removal and fastener installation.

According to one embodiment of the present disclosure, a surgical tool is provided with a housing, a cutter (end effector) support shaft that is operably connected to a motor to effect oscillating rotation of the shaft, and a drive transmission configured between the motor and the shaft to effect oscillating rotary movement of the shaft and cutter mounted to the shaft.

It is an objective of the present disclosure to provide such a surgical tool that utilizes a second transmission coupled between the first transmission and an end effector that is operable to selectively effect oscillating rotation in at least one rotational direction.

It is yet another objective of the present disclosure to provide such a surgical tool wherein the second transmission is operable to selectively effect non-oscillating rotation in one of two rotational directions.

It is a still further objective of the present disclosure to provide such a surgical tool with means to removably mount an end effector to an output coupler to allow the selective use of different end effectors.

Other objects and advantages of this disclosure will become apparent from the following description taken in conjunction with any accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this disclosure. Any drawings contained herein constitute a part of this specification, include exemplary embodiments of the present disclosure, and illustrate various objects and features thereof.

30 30 32 34 30 34 32 The reference numeraldesignates, generally, a rotary oscillating and reciprocating surgical tool useful, particularly, in the modification and/or removal of hard tissue, such as bone, cartilage and disc. The surgical toolis a handheld tool with a housingproviding a handlefor manually gripping the toolfor use during a surgical procedure. While one shape and style of handleis illustrated, any suitable shape and style of handle can be provided. For example, a right angle pistol grip may be added. Additionally, the housingmay have a narrow front portion for a smaller pencil–like “precision grip”, while the larger remaining portion is sized to balance in the user's hand, such as in the web area between the index finger and thumb, for allowing better control with less fatigue.

30 30 36 35 37 36 38 36 38 36 30 35 37 36 38 35 39 37 36 38 39 37 36 38 36 37 39 The toolcan be used in surgical operations such as spinal surgery, wherein tissue such as bone, cartilage and disc material that is preferably of a non-fibrous tissue type may be modified or removed, such as from the spine of a patient. The toolhas an output shaft 36, which is driven to rotate in an oscillating manner of two alternate directions about the longitudinal axis of the shaftby a first drive transmissionthat can have two drive components, including an oscillation effecting first driver. Shaftis provided with a surgical device, such as a cutting tool or driver bit, positioned and mounted to a distal end portion of the shaft. The cutting tool, or end effector,is driven to rotate in alternate directions (oscillation) like the shaft, with a limited range of angular displacement of rotation, for example, between about 90° and about 180°. It has been found that such oscillatory rotation is effective in cutting or modifying hard tissue like bone, cartilage and portions of discs. It has also been found that this oscillatory rotation reduces the risk of damage to fibrous tissue, such as muscle and nerve. The toolis provided with the first transmissionwhich includes the driverto effect the oscillating rotation of the shaftand its attached surgical device. The transmissioncan be provided with a reciprocation effecting second drivercoupled to the first driverto simultaneously effect reciprocating motion of the shaftand surgical devicewhile they are oscillating in rotation. The second driveruses the oscillating output of the first driverto add the reciprocating motion to the shaftand cutting tool. Reciprocating movement is parallel to the longitudinal axis of the shaft. The first driveris upstream operationally of the second driver.

30 40 42 32 30 44 32 40 46 The toolcan receive energy for its operations from an external supply, such as a direct current power supply cord. A power control switchcan be provided on the housingfor controlling the operation of the tool, such as in an ON and OFF manner and/or in a variable speed manner. A light sourcemay also be provided on the housingfor illuminating the surgical site. Such a light source may be a light emitting diode (LED), which can be powered directly or indirectly by energy from the cord. Energy can also be provided by a batteryor other energy storage device. The battery can be rechargeable or non-rechargeable.

2 FIG. 30 46 32 46 40 48 32 30 50 32 30 46 46 40 52 52 illustrates internal components of the tool. An energy source can be provided by a battery supplymounted in the housing. The battery supply, if rechargeable, can be charged by the power cord. Electronicsare provided in the housingfor controlling the operation of the tool. A plurality of indicator lampsmay also be provided on the housingand can be LEDs for indicating operational characteristics of the tool, such as the state of charge of the battery supply. Alternately, the batteriescan be eliminated in favor of the cordbeing connected to a source of electrical energy. Preferably, the power supply is low voltage, e.g., 12 volts. Additionally, the motorcan be powered by compressed air, a vacuum, or any other suitable source of energy that would, on demand, effect rotation of a rotor portion of the motor.

52 32 36 52 32 52 35 37 39 37 52 36 39 37 52 36 36 57 32 59 37 39 59 39 36 36 32 52 30 1 FIG. The motoris suitably mounted in the housing, wherein a portion of the motor, a rotor (not shown), is free to rotate and ultimately drive the shaft. A portion of the motoris fixed against rotation in the housingas is known in the art; for example, a motor housing and/or stator. The motordrives the shaft 36 through the first transmissionand its drivers,. The first driveris operable for converting continuous rotary motion from the motorto rotary oscillation of the shaft. The second driver, if included to provide reciprocating movement, is operable for converting continuous oscillation from the first driverand continuous rotation of the motor, and adds continuous reciprocating longitudinal movement to the shaft. The shaftis suitably mounted in the noseof the housing, as in one or more bearings. Operationally, the first driveris upstream of the second driver. The journal bearingsneed to accommodate both rotary and linear movement (if the second driveris utilized) of the shaft, and a suitable bearing is a journal bearing. The shaftmay be angled relative to the longitudinal axis of the housing, as depicted in, for ergonomics. Cooling fins, or a cooling fan, (not shown) may be attached to or near the motorfor cooling the motor and/or the tool.

3 18 FIGS.- 37 39 illustrate different forms of driversand.

37 32 39 36 52 60 52 36 36 35 37 39 37 60 52 36 39 3 4 FIGS.- The first driver, as best seen in, is positioned in the housingand operably couples the second driver, and hence shaft, to the motor, and is operable to convert the continuous rotary motion of the shaftof the motorto oscillating rotary motion of the shaft. By oscillating rotary motion, it is meant that the shaftwill rotate a portion of a complete revolution first in one rotation direction and then in the other rotation direction, first counterclockwise, then clockwise, then counterclockwise again, and so on. To effect this movement, the transmissioncomprises the two driver components,. The first driveris operable to convert the rotary motion of the shaftof the motorto oscillating rotary motion of the shaft, and the second driveris operable to convert that oscillating motion to reciprocating linear motion while maintaining the oscillating motion.

37 65 66 67 65 66 65 60 60 65 68 67 66 70 67 68 70 60 In the illustrated embodiment, the first transmission driverincludes a ball bearing having an inner race, an outer raceand a plurality of bearing ballscontained in the races,. The inner raceis secured to the motor shaftfor rotation thereby about the central axis of the motor shaft. In the illustrated embodiment, the inner raceis in the form of a sphere, with a groovetherein, and sized to receive and retain the ballstherein. The outer raceis in the form of a ring, having a grooverecessed in the inner surface thereof, and sized to receive and retain the ballstherein. The grooves,open toward one another and are positioned in a plane P that is set at an angle A relative to the longitudinal axis of the motor shaft. The angle A is the smallest angle between the plane P and shaft axis since the angle of the plane P relative to the shaft axis changes depending on the position from which the measurement is taken. The angle A is in the range of between about 30° and about 80°.

66 73 74 66 75 76 73 77 32 77 78 37 66 73 73 32 79 73 73 73 81 79 80 81 37 65 52 80 36 39 36 5 FIG. The outer raceis coupled to an oscillating connector, as for example with a pair of opposed pivot pinsprojecting outwardly from the outer raceand each being received in a respective borein a respective boss. The connectoris restrained in movement to a plane. In one example, a guide() is secured to the housing. The guideis curved, and is received in a similarly curved slotcooperating with the driver. Thus, the outer racecan only move in an oscillating manner, as can the connector. Another means to mount the connectoris with a pivot pin secured to the housingand extending through a web portionof the connector, which allows the connectorto rotate in an oscillating manner. The illustrated connectorhas a curved gear rack portion, preferably a sector gear, coupled to the weband carried thereby. A gear or gear segment, herein a gear, such as a bevel gear, engages the rack portionof the driverand itself is driven in an oscillating manner by rotation of the inner raceas driven by the motor. The gearis coupled to the shaftby the second driverto effect driving of the shaftin an oscillating manner.

80 52 80 The angle A determines the degree of rotation of the gear, and the rotational speed of the motordetermines the oscillation rate of the gear.

80 39 36 36 38 80 90 32 91 32 80 81 52 36 94 94 94 36 90 94 36 90 36 36 36 38 36 59 32 57 94 36 94 90 36 94 36 94 95 96 36 96 98 94 36 36 6 6 FIGS.A-C 4 5 FIGS., 4 6 FIGS.,A 8 FIG. 6 6 FIGS.A-C 6 FIG.A 6 FIG.B 6 FIG.C The gearis part of the second driver, and is coupled to the shaftto effect motion of the shaftand associated cutting toolas described herein. As shown, the gearis fixed to a shaftthat is rotatably mounted to the housingvia a suitable bearingfixed in position in the housing. The gearis maintained in driving engagement with the rack, which oscillates along a curved path during operation of the motor. The shaftis secured to a reciprocation effecting jointin a manner allowing part of the jointto pivot during rotation of the jointand shaft. See. Oscillation of the shaftand the jointeffects oscillation of the shaft. The longitudinal axis of the shaftintersects the longitudinal axis of the shaft,, and the axes are positioned at an angle B relative to one another. By being positioned at an angle B, which is preferably in the range of between about 5° and about 45°, the shaft, during oscillating rotation, will move longitudinally in two directions, effecting reciprocal movement of the shaftand cutting toolduring their oscillating movement. To allow for both oscillation and reciprocation, the shaftcan be mounted in one or more journal bearingsfixed in position in the housingand/or nose. The jointacts as a wobble plate because of the angle B. Additionally, to effect the reciprocating movement, the shaftis secured to the jointat a position offset radially outwardly from the center of its rotation, the center of the shaft,. This offset dimension D also determines the amount of reciprocating movement of the shaft. In a preferred embodiment, the jointoscillates about 180° and starts at a rotational position, where the shaftis at its most retractable position and ends at its most extendable position. The joint, as shown, includes a tabon which is mounted a ball or spherical bearing. The shaftis coupled to the bearingas with a pin,.illustrate the jointin three different rotary positions and three different reciprocating positions. In, the shaft is in its most extended reciprocating position.shows the shaftin an intermediate extended position.shows the shaftin its most retracted reciprocating position.

10 FIG. 36 39 101 94 102 104 105 105 90 91 36 102 101 94 illustrates another embodiment of connecting the shaftto the second driver. The reciprocating effecting jointis used instead of the joint. A pivot pinis mounted for rotation in a clevis, which in turn is mounted to a crank member. The crank memberis mounted to a shaft, which is rotatably mounted in the bearingas described above. The shaftis secured to the pivot pin. This form of jointis similar in operation to the jointas described above.

11 12 FIGS., 14 FIG. 39 36 36 90 120 36 122 126 122 128 32 57 128 126 36 37 36 120 128 126 120 illustrate another embodiment of a second driverthat is operable to effect longitudinal reciprocating movement of the shaft. The shaftis coupled to the shaftrelative to longitudinal movement therebetween, as for example, by the use of a spline connection, as can be seen in. An inner bearing raceis secured to the shaftand has an outwardly opening helical bearing groove. A plurality of bearing ballsare contained within the groove. An outer bearing raceis mounted in the housingor noseand is fixed against movement relative thereto. The outer bearing racehas a helical groove (not shown) that opens inwardly and contains the bearing ballstherein. When the shaftrotates in an oscillating manner, as effected by the first driver, the shaftwill move in a longitudinal reciprocating manner by cooperation between the inner and outer bearing races,, respectively, via the bearing balls. This forces the inner raceto move longitudinally in a reciprocating manner.

13 16 FIGS.– 14 FIG. 13 14 FIGS., 39 36 152 36 36 37 36 154 156 90 36 37 39 152 160 160 160 160 32 57 160 170 152 172 36 176 178 180 181 176 152 184 186 180 181 184 178 180 181 184 160 160 190 184 192 160 160 illustrate a further embodiment of a second driverthat is operable to effect longitudinal reciprocating movement of the shaft. This embodiment uses a helical bearingto effect longitudinal reciprocating movement of the shaftwhile the shaftis being rotationally oscillated by the first driver. As seen in, the shafthas its proximal endmale splined and is longitudinally movably received in a female splined socketwithin the shaft. Thus, the shaftcan move both longitudinally and rotationally while being driven by the drivers,. The helical bearingincludes a split housinghaving housing portionsA andB. The housingis mounted in the housingand/or its nosein a manner to prevent relative rotation therebetween. This can be accomplished, as seen in, by providing the housingwith a laterally projecting key. The bearinghas an inner racesecured to the shaftand provides a radially projecting helically longitudinally extending flange. Bearing ballsare positioned on opposite faces,of the flange. The helical bearingis provided with a pair of outer racesthat have a plurality of bearing ball receiving pocketsin the faces opposite the faces,. The outer racesretain the bearing ballsin contact with their respective faceor. Rotation of the outer racesrelative to the housing portionsA andB is limited by stop faceson the outer races, and stop faceson the inside of the housing portionsA andB.

8 9 FIGS., 5 6 6 FIGS.,A-C 37 37 52 201 60 201 203 204 203 201 201 203 210 32 211 213 215 215 211 215 217 219 211 215 215 203 220 203 210 120 39 36 225 210 80 210 36 39 36 illustrate a second embodiment of the first driver. It is similar to the drivershown in. The motorhas a crank assemblymounted on its output shaft. The crank assemblyincludes a drive armthat can include a wear resistant bearing member. The drive armis offset radially from the center of rotation of the crank assembly. Thus, rotation of the crank assemblymoves the drive armin a circular path. A follower assemblyis mounted in the housingin a manner to restrict its movement in a plane laterally from side to side. As shown, a guide bedis provided and includes a guide channel, which receives in it a guide rail. As shown, the guide railis coupled to the bedto prevent their separation during movement. As illustrated, the guide railhas a pair of opposed grooves, in each of which is received a respective guide railto provide guided restrained movement between the guide bedand guide rail. The guide railis straight, thereby restricting movement of the follower assembly to linear movement in a plane. The drive armis received in a channelwith a close fit, whereupon revolving movement of the drive armwill effect reciprocating lateral movement of the follower assembly. The follower assemblyis drivingly coupled to the second driverin a manner to effect oscillating rotation of the shaft. As shown, a gear rackis provided on the follower assemblyto mesh with the gear, whereby lateral movement of the follower assemblyeffects oscillating rotation of the shaft, which, with operation of the second driver, will simultaneously effect reciprocating motion of the shaft.

7 7 FIGS.A-M 17 18 18 FIGS.,A-D 37 39 37 36 36 illustrate another form of drivers,. The first driveris illustrated as a Cardan type drive that is operable to effect rotary oscillation of the shaft. While the structure shown in these Figures effects only oscillating rotation, the additional structure shown inshows a mechanism to convert the oscillating rotation into oscillating rotation and linear reciprocation of the shaft.

7 7 FIGS.A-I 7 7 FIG.B-I 17 FIG. 300 304 300 304 300 304 306 52 306 304 304 300 304 308 52 308 300 308 illustrates the basic functioning of a Cardan mechanism. An internal gear memberhas an external gearreceived therein. The gear ratio between the internal gearand the external gearis 2:1. The gear, in this case, is fixed against movement, while the gearis part of a crank armmounted to the motor. As the crank armeffects revolving of the gearabout the center of rotation of the motor shaft, the gearmoves about the interior of the internal gear. The gearhas secured thereto an output armthat has a center of rotation that is coaxial with the center of rotation of the motorwhen the armis at its center position within the gear, as seen in. In this type of mechanism, the center of the armmoves in a linear path in a laterally reciprocating manner. Thus, rotary output motion of the motor shaft can be converted into reciprocating linear motion. This can be seen in.

7 7 FIGS.J-M 7 FIG.A 37 320 308 36 320 308 52 308 320 322 32 57 308 320 325 320 322 325 322 325 327 36 320 322 36 As seen in, the Cardan style first driveris coupled to a followerthat is operable to convert the linear movement of the arminto oscillating rotary motion of the shaft. The illustrated followerreceives the armin an elongate slot (not shown) on the side facing the motor; this allows the armto move freely as the followerpivots about a pair of pivot pinsthat are mounted in suitable bearings (not shown) in the housingand/or its nose. As the armmoves laterally, as seen in, it will force the followerto pivot. A curved gear racksecured to the follower, is preferably integral therewith, and has the gear teeth spaced radially outwardly from the pivot pins. The radius of the gear rackis substantially the radial distance of the gears from the center of rotation of the pivot pins. The gear rackis meshed with a gear or gear segment, such as a spur gear, that is secured to the shaft. As the followeroscillates about its pivot pins, the shaftis driven in a rotary oscillating manner.

17 18 18 FIGS.andA–D 7 7 FIGS.J-M 18 18 FIGS.A–D 39 37 325 339 327 36 308 304 327 36 340 340 341 343 345 341 36 59 343 341 341 343 350 343 345 350 327 339 340 36 illustrate a still further embodiment of a second driver. It utilizes a Cardan first driver, such as shown in. However, instead of a curved gear rack, this form uses a straight gear rack, and the gearwhich is coupled to the shaftmoves laterally with its center of rotation being in a straight line. This can be accomplished by having the armcentered on the center of rotation of the gear. The gearis coupled to the shaftthrough the use of a drive shaft. As shown, the drive shafthas three sections,, and. Sectionis secured to the shaft, which, in turn, is mounted in the bearing, as described above. Sectionis coupled to sectionin a manner that allows the axes of sectionsandto change their angular orientation. This can be accomplished by a universal joint (u–joint). Sectionis coupled to sectionin a similar manner, as with a second universal joint. As the gearrotates and moves laterally side-by-side on the gear rack, the length of the drive shaftincreases and decreases, effecting linear reciprocating movement of the shaft. This can be seen in.

19 21 FIGS.- 19 21 FIGS.- 5 6 6 FIGS.,A-C 35 37 39 35 52 401 60 401 403 404 403 401 401 403 410 32 406 406 410 405 32 410 407 408 404 408 404 404 410 404 403 52 410 403 413 414 404 413 404 404 403 413 408 410 411 406 407 411 406 406 415 410 416 36 416 411 36 32 59 411 406 36 410 52 403 illustrate another embodiment of the first transmission, first driverand second driver. The transmissioninis similar to that shown in, in that it uses both a rack and pinion gear drive arrangement and a crank assembly. The motor, described above, has a crank assemblymounted on its output shaft. The crank assemblyincludes a drive armthat can include a wear resistant bearing member. The drive armis offset radially from the center of rotation of the crank assembly. Thus, rotation of the crank assemblymoves the drive armin a circular path. A follower assemblyis mounted in the housingin a manner to restrict its movement in a plane laterally from side to side in a pivoting manner about an axle arrangement. The axle arrangementis mounted for pivoting movement of follower assemblywith suitable bearingsmounted in the housing. The follower assemblyhas a pair of spaced apart arms, each with an inwardly opening channelsized and shaped to receive the bearing membertherein. The channelsare portions of a cylinder and the bearingis a cylinder, allowing the bearingto move both longitudinally and rotationally relative to the follower assembly. The bearingis mounted to the drive armin a manner to allow the drive arm to be rotated by the motorand effect rotational pivoting movement of the follower assembly. As shown, the drive armis provided with a generally spherical bearingmounted in a spherical cavityin the bearingthat permits multi axis rotation of the bearingrelative to the bearing. The bearingis in the form of a ball joint. When the drive armis driven so the bearingmoves in a circular path, the bearing moves longitudinally in the channels, as well as rotationally. The follower assemblyis provided with a gear rackforward of the axle arrangementfrom the arms. The rackis preferably a sector gear and is preferably curved, having an inner edge curved in a circular arc with a radius approximately equal to its spacing from the center of rotation about the axle assemblyand an outer edge curved in an arc with a radius approximately equal to its spacing from the center of rotation about the axle assembly. The gear tooth surfaceis beveled relative to the plane of rotation of the follower assembly. This accommodates its driving a pinion gearmounted to the shaftto which it is mounted. The gearis a bevel gear that has gear teeth that mesh with the gear teeth of the rack. The shaftis mounted in the housingvia bearingsas described above. The rackrotates in two directions about the axle assemble, which effects oscillating rotation of the shaft, also in two directions. Thus, the follower assemblyconverts one directional rotation of the motorand drive arminto two direction oscillatory rotation.

The term gear, bevel gear, curved gear rack, and gear rack as used herein includes both complete gears and gear segments.

22 FIG. 30 36 30 30 32 52 35 536 35 52 36 536 35 521 571 521 36 36 521 536 521 571 illustrates a further embodiment of the present disclosure. It is configured to allow for multiple modes of operation of the output of the tool. It will allow for the above described outputs of the first shaft, in rotary oscillation shaft motion. The toolis constructed to provide for both the above oscillating rotary operation of an end effector, and for unidirectional rotation of an end effector. The toolincludes a housingand a motormounted in the housing. It also includes a first transmissionand a second transmission. The first transmissionis coupled to the motorand is operable to selectively effect rotary oscillating motion of the first shaftand of an end effector. The second transmissionis operable to selectively convert the oscillating rotation output of the first transmissionto unidirectional rotation of an end effector. The second transmission includes an output shaftand coupling means such as couplerconfigured to couple with an end effector. The output shaftis coupled to the first shaftand is fixed against relative rotation between the first shaftand the output shaft, but allows relative longitudinal movement therebetween. The second transmissionincludes at least one sprag clutch operable to allow the first driver to selectively effect oscillating rotation of the output shaftand the couplerand unidirectional rotation of the coupler in a selected unidirectional direction of rotation.

35 37 32 501 57 501 503 505 57 503 501 57 503 505 501 32 In a preferred embodiment, the first transmissioncan utilize the first driver. In the preferred embodiment, housingincludes an enclosureas part thereof, and has the noseoperably associated therewith. As shown, the enclosureincludes a proximal end sheath portionand a distal end sheath portion. As shown, the noseis at the distal end of the sheath portionof the housing. As shown, the nose, and sheath portions,are threadably connected, but other suitable connections can be provided. Additionally, the three described portions can be of a single piece construction. It is also noted that the enclosurecan be connected to the housingin any suitable manner for a multi piece construction or can be integral therewith.

36 501 36 59 501 507 509 511 501 513 511 501 511 36 36 511 515 512 511 517 509 517 511 The shaftis movably rotatably mounted in the enclosure. The shaftis shown as mounted in the bearings, which are in turn mounted in the enclosurein a bore. As illustrated, the shaft 36 has a flangepositioned on its free distal end. A sleeveis mounted in the enclosure, preferably for both rotational and reciprocating longitudinal motion. One or more bearings, such as roller bearings, accommodate the movements of the sleevewithin the enclosure. The sleeveis coupled to the shaftsuch that the shaftcan effect the movement(s) of the sleeve. In one embodiment, the coupling can be via a splined connection with splinesprojecting inwardly from an interior surface defining a through boreof the sleeveand splinesprojecting outwardly from an exterior surface of the flange. The splinesinterengage to accommodate rotational and reciprocating longitudinal motion of the sleeve.

511 521 501 536 523 525 523 525 512 511 511 511 523 525 521 521 523 525 521 521 531 521 533 523 525 535 523 525 521 531 521 533 541 521 523 525 523 525 511 533 535 Means is provided to effect coupling of the sleeveto an output shaftalso carried by the enclosure. In the illustrated embodiment, the second transmissionincludes a pair of sprag clutchesand. A sprag clutch is a one-way freewheeling clutch. In one direction, rotation between an inner race and an outer race is allowed; while in the opposite direction of rotation of an inner race to an outer race, relative rotation between the inner and outer race is prohibited. As shown, the sprag clutches,are mounted in the boreof the sleevewith the outer races thereof being fixed against movement relative to the sleeve, while the inner races are permitted to move relative to the sleeveas described below. The sprag clutches,are also mounted to the output shaftin a manner to allow relative movement longitudinally of the shaft. The sprag clutches,are keyed to the shaftto selectively prevent and allow relative rotation between their inner races in the shaft. The keyed mode of coupling can be provided by having a proximal free end portionof the shaftsplinedon an outer surface while the inner surfaces of the inner races of the sprag clutches,are also splined, allowing relative longitudinal movement of the sprag clutches,to the shaft. As shown, the proximal endof the shafthas an enlarged diameter portion where the splinesare located and a decreased diameter portionthat is small enough to prevent contact of the shaftwith the inner race of the sprag clutches,. The sprag clutches,are mounted in the sleevein longitudinally spaced apart relationship. The splines,can have tapered lead in sections to facilitate their selectively interengagement.

511 501 523 525 531 511 551 553 551 501 555 551 553 557 557 559 501 555 511 501 555 501 501 The sleeveis selectively longitudinally movable within the housingto effect which sprag clutch,will drive the output shaft. As shown, the sleeveis provided with an exterior annular grooveopening outwardly. A split annular ringis mounted in the grooveand fits within the enclosure. An operatoris positioned on the exterior of the housingand is attached to the ringas with a threaded fastener. The fastenerextends through an elongate slotthrough the housing. The operatoris operable to selectively move the sleevelongitudinally relative to the housingand allows the sleeve to rotate within the housing. Means (not shown) such as a detent can associate the operatorwith the enclosureto selectively fix the operator in a selected position relative to the enclosurethat sets the operating mode.

521 501 561 505 521 521 571 57 57 505 573 571 575 38 30 581 575 505 The shaftis rotatably mounted in the housingas with bearingsmounted in the sheath portionand on the shaft. The shaftis provided with coupling means, designated generallythat are positioned in the nose. As shown, the noseis mounted to the sheath portionas by a threaded interengagement at. The means, as illustrated, includes a couplerthat can be in the form of a hex socket or square socket having detent means (not shown) to secure a surgical deviceto the tool. In the illustrated structure, a thrust bearingcan be provided to reduce operational friction between the couplerand the sheath portion.

22 FIG. 22 FIG. 52 411 412 36 36 511 501 531 525 533 531 531 525 531 523 533 531 411 531 411 411 531 531 555 523 525 533 531 523 525 531 531 52 523 525 555 In operation, as seen in, the motoris actuated, which in turn drives the rack, which in turn drives the gear, which in turn effects reciprocating rotation of the shaft. The shaftthen effects rotation of the sleevein the enclosure. To effect intermittent rotation of the shaftin a first direction, the sprag clutchis engaged on the splineof the shaft, as illustrated in. To effect intermittent rotation of the shaftin a second and opposite direction, the sprag clutchis moved longitudinally aft to disengage the shaftand engage the other sprag clutch bearingon the spline. This then effects intermittent rotation of the shaftin the opposite direction. During the unidirectional rotations, as just described, there is a pause in the rotation while the rackmoves in its non-driving direction, which will provide an impact to the shaftfrom the change in direction of rackmovement. In other words, the rackdrives during only one half of its complete motion cycle. This effects unidirectional motion either clockwise or counterclockwise of the shaft. To effect bidirectional oscillating rotation of the shaft, the operatoris moved to a position whereby both sprag clutches,are engaged with the splineof the shaft, allowing both sprag clutches,to effect bidirectional oscillating rotation of the shaft. To effect selection of rotation of the shaft, the motorwill need to be deenergized to allow repositioning of a sprag clutch,with the operator.

23 23 24 FIGS.A -C and 22 FIG. 30 35 536 30 52 52 601 57 601 603 57 52 603 501 57 603 603 52 illustrate a further embodiment of the tool, which is similar in operations to the tool described above in regard toand includes a first transmissionand a second transmissiongenerally as described above. The toolincludes a housing, also as described above. The housingincludes an enclosureas part thereof and has the noseoperably associated therewith. As shown, the enclosureincludes a sheath. As shown, the noseis part of the housingand located at the distal end of the sheathof the enclosure. As shown, the noseand sheathare threadably connected, but other suitable connections can be provided. The sheathis suitably mounted to portions of the housing.

36 411 412 36 59 59 610 603 511 655 603 555 655 656 612 A shaftis operably coupled to the rackvia a gearas described above. The shaftcan be rotatably mounted in a plurality of bearings. As shown, two of the bearingsare mounted in a bearing blockthat is in turn mounted in sleeve, which is similar in construction and operation to the above described sleeve. An operatoris movably mounted on the sleeve, and is similar in operation and construction to the operator. The operatorincludes a fingerthat is movable along the length of the slotfor a purpose described below.

36 631 632 36 631 632 36 636 634 631 36 631 631 623 625 623 625 637 671 626 631 637 671 631 634 673 671 655 631 675 631 677 655 675 675 631 679 The shaftis coupled to a second shaftto effect oscillating rotation thereof. The distal end portionof the shaftkeys to the second shaftin a manner to prevent relative rotation, while allowing relative longitudinal movement therebetween. As shown, the distal end portionof shaftis generally square atand is received in a corresponding square boreof the shaft. This arrangement allows for relative longitudinal movement between the shaftsandwhile preventing relative rotation. The shaftis mounted in at least one, and preferably a pair of sprag clutches,. The use of a single sprag clutch will permit only one direction of unidirectional rotation, while a pair of sprag clutches will permit unidirectional rotation of an end effector in two directions. The sprag clutches,are secured in a borein the coupling meansin a manner to eliminate relative movement therebetween. An idle bearingalso rotatably supports the shaftand is mounted in the borecoupling means. As shown, the shafthas an enlarged diameter portionfor a purpose later described. A thrust bearingcan be provided to reduce friction when a coupling meansis being operated as described below. The operatorcouples to the shaftvia a bearingfixed to the shaft. A retainer portionof the operatorcouples to the bearing. The bearingcan be attached to the shaftvia a retainer, such as a C-clip.

631 671 671 36 671 631 671 672 631 671 52 631 655 634 623 623 671 36 411 631 655 634 625 623 36 623 631 623 625 36 671 38 23 FIG.A 23 FIG.A 23 FIG.B 23 FIG.C The shaftselectively couples to the coupling meansto provide for three different modes of driving of the coupling meansby the shaft. As seen in, the coupling meansis drivingly coupled to the shaftto provide a direct drive to effect bidirectional oscillating rotation of the coupling means. The coupling can be by a splined connection, a key connection or the like at, but allows relative movement between the shaftand the coupling means. This engagement should preferably be made when the motoris deenergized. Movement of the shaftfrom the mid position, shown in, to a forward position, as seen in, through operation of the operator, disengages the spline connection and moves the enlarged diameter portioninto the sprag clutch. The sprag clutchis oriented such that it will drive the coupling meansonly in one direction during one half of a complete cycling of the bidirectional rotation of the shaftby the rack. Upon movement of the shaftto a rear position with the operator, as seen in, the enlarged diameter portionmoves into engagement with the sprag clutch; which is oriented for freewheeling in the opposite direction of that of sprag clutch. This will then effect rotation in only one direction during one half of a complete rotation cycle of the shaft, and is directionally opposite to that described when the sprag clutchis operational. The shaftfunctions as an inner race for the sprag clutches,. As described above, a change in direction of rotation of the shaftwill provide an impact to the coupling meansand an attached surgical device.

671 57 681 681 673 671 671 676 575 As shown, the coupling meansis rotatably mounted in the nose, as with a sleeve bearing. The bearings,capture the coupling meanstherebetween, limiting its longitudinal movement. The coupling meanscan be in any suitable form and can include a socketsimilar in construction and operation to the socketdescribed above.

All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the disclosure pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.

It is to be understood that while a certain form of the disclosure is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the disclosure and the disclosure is not to be considered limited to what is shown and described in the specification and any drawings/figures included herein.

One skilled in the art will readily appreciate that the present disclosure is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary, and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the disclosure and are defined by the scope of the appended claims. Although the disclosure has been described in connection with specific preferred embodiments, it should be understood that the disclosure as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the disclosure which are obvious to those skilled in the art are intended to be within the scope of the following claims.